Smoking is not recommended for patients with high blood sugar. Smoking will affect blood vessels, respiratory system and many other organs and tissues, aggravate the damaging effect of high blood sugar on blood vessels, prone to diabetic nephropathy, atherosclerosis and other diseases. Hyperglycemia is an unfavorable factor for cardiovascular and cerebral vessels, long-term hyperglycemia is prone to diabetic nephropathy, diabetic retinopathy, diabetic neuropathy, atherosclerosis and other diseases. At the same time smoking itself for the endothelium will have some damage, high blood sugar people smoking will increase the probability of vascular disease. Therefore, smoking is not recommended for people with high blood sugar, and they should develop good habits and monitor their blood sugar regularly.